Biomaterial Database

An unusual heparin-binding peptide from the carboxy-terminal hep-2 region of fibronectin. 1994

K C Ingham, and S A Brew, and M Migliorini

Holland Laboratory, American Red Cross, Rockville, Maryland 20855.

A synthetic 22 residue peptide, N22W, with sequence NVSPPRRARVTDATETTITISW, derived from the amino terminus of type III module 13 in the carboxy-terminal hep-2 domain of fibronectin, was found to exhibit unusual heparin binding properties. Titration of fluoresceinamine-labeled heparin (FA-heparin) with N22W at 25 degrees C and pH 7.4 in 0.02 M Tris buffer containing 0.15 M NaCl (TBS) produced a cooperative sigmoidal increase in fluorescence polarization anisotropy with half-saturation near 2.5 microM. The increase in anisotropy was even greater than that produced by the much larger 30-kDa hep-2 fragment of fibronectin and saturation was achieved at lower concentration. Simply deleting the C-terminal Trp from the peptide abolished its heparin-binding activity as did deletion of residues TETTITIS or mutation of the RR doublet to SS. Further analysis suggested that peptide-peptide interactions mediated by the carboxy-terminal region of N22W play an important role in its binding to heparin. A branched tetrameric peptide containing four copies of N21S caused a nearly hyperbolic increase in anisotropy of FA-heparin with an apparent Kd of 0.3 microM in TBS, 10-fold lower than that of the monomer or of the parent domain from which the peptide was derived. The results illustrate that peptide-peptide interactions can lead to stronger binding by allowing multiple points of contact with the negatively charged polysaccharide.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D002846	Chromatography, Affinity	A chromatographic technique that utilizes the ability of biological molecules, often ANTIBODIES, to bind to certain ligands specifically and reversibly. It is used in protein biochemistry. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Chromatography, Bioaffinity,Immunochromatography,Affinity Chromatography,Bioaffinity Chromatography
D005353	Fibronectins	Glycoproteins found on the surfaces of cells, particularly in fibrillar structures. The proteins are lost or reduced when these cells undergo viral or chemical transformation. They are highly susceptible to proteolysis and are substrates for activated blood coagulation factor VIII. The forms present in plasma are called cold-insoluble globulins.	Cold-Insoluble Globulins,LETS Proteins,Fibronectin,Opsonic Glycoprotein,Opsonic alpha(2)SB Glycoprotein,alpha 2-Surface Binding Glycoprotein,Cold Insoluble Globulins,Globulins, Cold-Insoluble,Glycoprotein, Opsonic,Proteins, LETS,alpha 2 Surface Binding Glycoprotein
D005452	Fluoresceins	A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays.	Tetraiodofluorescein
D005454	Fluorescence Polarization	Measurement of the polarization of fluorescent light from solutions or microscopic specimens. It is used to provide information concerning molecular size, shape, and conformation, molecular anisotropy, electronic energy transfer, molecular interaction, including dye and coenzyme binding, and the antigen-antibody reaction.	Anisotropy, Fluorescence,Fluorescence Anisotropy,Polarization, Fluorescence,Anisotropies, Fluorescence,Fluorescence Anisotropies,Fluorescence Polarizations,Polarizations, Fluorescence
D005456	Fluorescent Dyes	Chemicals that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.	Flourescent Agent,Fluorescent Dye,Fluorescent Probe,Fluorescent Probes,Fluorochrome,Fluorochromes,Fluorogenic Substrates,Fluorescence Agents,Fluorescent Agents,Fluorogenic Substrate,Agents, Fluorescence,Agents, Fluorescent,Dyes, Fluorescent,Probes, Fluorescent,Substrates, Fluorogenic
D006493	Heparin	A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.	Heparinic Acid,alpha-Heparin,Heparin Sodium,Liquaemin,Sodium Heparin,Unfractionated Heparin,Heparin, Sodium,Heparin, Unfractionated,alpha Heparin
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships